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POLAR BEARS

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The polar bear (Fig. 1) is the largest member of the family Ursidae. Males are approximately twice the size of females. On average, adult males weigh 500 to 900 pounds (250 to 400 kg), depending on the time of year. An exceptionally large individual might reach 1,320 to 1,760 pounds (600 to 800 kg).
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Content Preview
Peter L. Clarkson
Wolf/Grizzly Bear Biologist
POLAR BEARS
Renewable Resources
Government of the N.W.T.
Inuvik, Northwest Territories
Canada X0E 0T0
Ian Stirling
Polar Bear Biologist
Canadian Wildlife Service
Edmonton, Alberta
Canada T6H 2S5
Fig. 1. Polar bear, Ursus maritimus
Damage Prevention and
Store garbage, human waste, food, and
Vehicles, heavy construction
Control Methods
other products in areas not
equipment, snowmobiles, and
accessible to bears.
helicopters can be used to chase
polar bears away from work and
Exclusion
Deterrents and Frightening
living areas.
Devices
Heavy woven-wire fences (minimum
Detection Systems
6 feet [2 m] tall).
Loud noises, vehicle engines, cracker
shells, rifle shots, barking dogs, and
Dogs, bear monitors, trip-wire
Specifically designed electric fences.
air horns.
fences, and electronic (infra-red,
High metal walls (offshore oil rig
microwave, modulated light beam)
Trained bear dogs.
caisson or drilling ship).
alarm systems.
Employ trained bear monitors with
Sturdy metal buildings and iron cages.
Constant vigilance of personnel
firearms and deterrents to protect
working at the site.
Cultural Methods
communities, industry camps, and
work places.
Repellents
Remove snow around buildings and
work areas to increase visibility.
Nonlethal firearm deterrents such as
Capsaicin spray.
12-gauge plastic slugs and 1 1/2-
Install good lighting in areas where it
Toxicants
inch (38-mm) rubber bullets.
is essential to detect bears that may
None are registered.
be in the vicinity.
PREVENTION AND CONTROL OF WILDLIFE DAMAGE — 1994
Cooperative Extension Division
Institute of Agriculture and Natural Resources
University of Nebraska - Lincoln
United States Department of Agriculture
Animal and Plant Health Inspection Service
Animal Damage Control
C-25
Great Plains Agricultural Council
Wildlife Committee

Fumigants
None are registered.
Trapping
Live traps (culvert and barrel traps)
and snares (Aldrich foot snares).
Shooting
Twelve-gauge shotgun and rifled slugs
at close range.
High-powered rifle of .30-06 caliber or
larger at close or long range.
Other Methods
Drugging and immobilization with
Alaska
Greenland
Telazol (safest and most reliable
drug) administered by a dart gun or
jabstick. Other drugs can be used
with suitable care.
Identification
Canada
The polar bear (Fig. 1) is the largest
member of the family Ursidae. Males
Fig. 2. Polar bear distribution map.
are approximately twice the size of
females. On average, adult males
weigh 500 to 900 pounds (250 to 400
kg), depending on the time of year. An
Range
ice, probably because of the low den-
exceptionally large individual might
sity of seals there.
reach 1,320 to 1,760 pounds (600 to 800
Polar bears are distributed throughout
Polar bears use a variety of habitats
kg). Adult females weigh 330 to 550
the circumpolar Arctic. In North
when hunting seals, including stable
pounds (150 to 250 kg) on average,
America, their range extends from the
fast-ice with deep snowdrifts along
although a pregnant female just prior
Canadian Arctic Islands and the
pressure ridges that are suitable for
to going into a maternity den could be
permanent multiyear pack ice of the
seal birth lairs and breathing holes, the
double that weight.
Arctic Ocean to the Labrador coast
floe edge where leads are greater than
and southern James Bay. The southern
Polar bears have a heavy build overall,
1 mile wide (1.6 km), and areas of
limit of their distribution in open ocean
large feet, and a longer neck relative to
moving ice with seven-eighths or more
areas such as the Bering Sea or Davis
their body size than other species of
of ice cover. Bears may be near the
Strait varies depending on how far
bears. The fur is white, but the shade
coast or far offshore, depending on the
south seasonal pack ice moves during
may vary among white, yellow, grey,
distribution of these habitats. Ringed
the winter (Fig. 2).
or almost brown, depending on the
seals (Phoca hispida) and sometimes
time of year or light conditions. The
bearded seals (Erignathus barbatus)
pelage consists of a thick underfur
Habitat
maintain their breathing holes from
about 2 inches (5 cm) in length and
freezeup in the fall to breakup in the
guard hairs about 6 inches (15 cm)
spring. Bears can hunt more success-
From freezeup in the fall, through the
long. Polar bears have a plantigrade
fully in areas where wind, water cur-
winter, and until breakup in the
gait and five toes on each paw with
rent, or tidal action cause the ice to
spring, polar bears are dispersed over
short, sharp, nonretractable claws.
continually crack and subsequently
the annual ice along the mainland
Females normally have four functional
refreeze.
coast of continental North America,
mammae. The vitamin A content of
the inter-island channels, and the shore
During winter, bears are less abundant
the liver ranges between 15,000 and
lead and polynia systems associated
in deep bays or fiords in which
30,000 units per gram and is toxic to
with them. Polar bears are not abun-
expanses of flat annual ice have con-
humans if consumed in any quantity.
dant in areas of extensive multiyear
solidated through the winter. In places
C-26

where the snow cover in the fiords is
eggs, sea weed, grass, and other veg-
cise and acclimatize to the cold, after
deep, large numbers of ringed seals
etation, although these food sources
which they move to the sea ice to hunt
give birth to their pups in subnivean
are much less common and probably
seals.
lairs in the spring. Consequently, polar
not significant.
The mean age of adults in a population
bears in general, but especially females
Polar bears are curious animals and
is 9 to 10 years and average life expect-
with newborn cubs, move into such
will investigate human settlements and
ancy is about 15 to 18 years. Maximum
areas in April and May to hunt seal
garbage. They have been observed to
recorded age of a male in the wild is 29
pups.
ingest a wide range of indigestible and
years. Few male polar bears live past
During summer, the response of the
hazardous materials, such as plastic
20 years because of the intense compe-
bears to the annual ice melts varies
bags, styrofoam, car batteries, ethylene
tition and aggression among them. The
depending on where they live. Bears in
glycol, and hydraulic fluid.
oldest age recorded for a wild female
the Beaufort and Chukchi seas may
polar bear is 32 years.
move hundreds of miles to stay with
General Biology,
Depending on the age and sex class,
the ice. Bears in the Canadian arctic
polar bears spend 19% to 25% of their
archipelago make seasonal movements
Reproduction, and
total time hunting in the spring and
of varying distances depending on ice
Behavior
30% to 50% of their time hunting in the
conditions. Polar bears travel season-
summer. Polar bears capture seals
ally to remain where ice is present
Polar bears mate on the sea ice in April
mainly by stalking them, by waiting
because they depend on the sea ice for
and May. Implantation of the embryo
for them to surface at a breathing hole
most of their hunting.
is delayed until the following Septem-
or, in the spring, by digging out seal
In Hudson Bay, James Bay, parts of
ber. The adult sex ratio is even, but
pups and sometimes adults from birth
Foxe Basin, and the southeastern coast
because females normally keep their
lairs beneath the snow. When a polar
of Baffin Island, the ice melts com-
young for about 2 1/2 years, they usu-
bear kills a seal it immediately eats as
pletely in the summer and there are no
ally mate only once every 3 years. This
much as it can and then leaves. Polar
alternate areas with ice close enough to
creates a functional sex ratio of three
bears do not cache food and normally
migrate to. In these areas the bears
or more males per female that results
only remain with a kill for a short time.
may be forced ashore as early as the
in intensive competition among males
In the case of a large food supply such
end of July to fast on land until
for access to estrus females.
as a dead whale or a garbage dump,
November. Some bears remain along
Maternity dens are usually dug in
individual bears may remain in an
the coast while others move inland to
deep snow banks on steep slopes or
area for several days or even weeks.
rest in pits in snow banks or in earth
stream banks near the sea by late Octo-
Polar bears sleep about 7 to 8 hours a
dens in areas of discontinuous perma-
ber or early November, depending on
day. They tend to be more active at
frost. By late September or early Octo-
the availability of snow. In the Beau-
“night” during the 24-hour daylight
ber, bears that spent the summer on
fort Sea, a large proportion of the
that prevails in the summer months,
land tend to move toward the coast in
females den on the multiyear pack ice
and to sleep during the day. Within 1
anticipation of freezeup. Many con-
several hundred miles (km) offshore.
or 2 hours after feeding, they will usu-
flicts with people occur in the fall
On the Ontario and Manitoba coasts of
ally sleep, regardless of the time of
when bears are waiting along coastal
Hudson Bay, female polar bears may
day. Before sleeping, females with
areas for the sea ice to form.
have their maternity dens 30 to 60
cubs often move away from areas
miles (50 to 100 km) or more inland,
where other bears are active, probably
Food Habits
though this is quite unusual elsewhere
to reduce the risk of predation on the
in polar bear range.
cubs by adult males.
Polar bears feed on ringed seals and to
Pregnant females normally have 2
a lesser degree on bearded seals.
young between about late November
Damage and Damage
About half of the ringed seals killed
and early January. At birth, cubs
during the spring and early summer
Identification
weigh about 1.3 pounds (0.6 kg), have
are the young of the year. These young
a covering of fine hair, and are blind.
seals are up to 50% fat by weight and
They are nursed inside the den until
Threat or damage from a polar bear
are probably easy to catch because
sometime between the end of February
differs from that of other bears because
they are vulnerable and inexperienced.
and the middle of April, depending on
it can occur at any time of the year.
Less frequently taken prey include
latitude. When the female opens her
Conflicts are commonly referred to as
walrus (Odobenus rosmarus), white
den, the cubs weigh 22 to 26 pounds
“threat to life or property” (TLP) or
whales (Delphinapterus leucas), nar-
(10 to 12 kg). The family remains near
“defense of life or property” (DLP).
whals (Monodon monoceros), and harp
the den, sleeping in it at night or dur-
Although polar bears are the most
seals (Pagophilus groenlandicus). Polar
ing inclement weather for up to
predatory of the three North American
bears also eat small mammals, bird
another 2 weeks while the cubs exer-
bears, their threat to human life has
C-27

been low. Historically, northern people
Damage Prevention and
vent bear problems (Clarkson et al.
(Inu, Inuit, Inuvialuit, and Inupiat)
Control Methods
1986b). The plan helps camp safety of-
were aware of the threat posed by
ficers, team leaders, and managers lo-
polar bears. Legends and artwork por-
Preventing Polar Bear-People
cate and design facilities and programs
tray conflicts between northern people
Conflicts
that are site specific. It contains infor-
and polar bears. In recent times, polar
mation and emergency contact tele-
bears have injured or killed people liv-
Preventing bear-people conflicts has
phone numbers, site design, personnel
ing and working in the Arctic. Fleck
been given considerable attention in
responsibilities, and techniques to
and Herrero (1988) provide a detailed
the Canadian and Alaskan Arctic since
detect and deter bears. The plan can be
discussion of polar bear-people con-
the mid-1970s. Reducing the number
included in the Safety in Bear Country
flicts in the Northwest Territories and
of polar bear-people conflicts has
Manual as an additional chapter. Prob-
other areas. The Bear-People Conflict
increased the safety of people living
lem Bear Site Operation Plans have
Proceedings (Bromley 1989) includes
and working in the Arctic and reduced
been developed for polar bear con-
several papers on handling and pre-
the number of polar bears killed in
cerns at the arctic weather stations and
venting encounters with bears.
problem situations. An active public
for oil exploration activities in the
information and education program
Beaufort Sea. Each plan deals with
Damage to property can be serious in
will help inform people how to pre-
being prepared for and preventing po-
the remote and sometimes harsh arctic
vent bear problems. Most wildlife
lar bear problems at specific sites.
environment, where food and shelter
agencies in bear country have a variety
may be essential to survival. Most
of public education materials available
Avoiding and responding to close
property damage occurs at small semi-
that are specifically designed to help
encounters with polar bears is
permanent hunting camps, industrial
people prevent bear problems and bet-
addressed by Bromley (1985), Fleck
camps, and in communities. Damage
ter handle any that may occur. Special
and Herrero (1988), Stirling (1988a),
includes destruction of buildings and
information and training workshops
and Graf et al. (1992). While each polar
their contents, predation of tied dogs,
have been developed by the Depart-
bear encounter is different, the chance
destruction of snowmobile seats and
ment of Renewable Resources, North-
of a serious or fatal bear problem can
other plastic or rubber products or
west Territories, and adopted by
be reduced by keeping alert and being
equipment, and raiding of food caches.
wildlife agencies and industry in other
informed and prepared to deal with
jurisdictions. The workshops instruct
any bear problems that may arise.
Legal Status
people on how to prevent bear con-
flicts. Two publications to assist work-
Exclusion
Polar bears are protected in Canada
shop instructors are available
Heavy woven-wire fences are effective
and the United States. In Canada,
(Clarkson and Sutterlin 1983, and
in keeping bears out of an area. Fences
polar bears are legally hunted. Sea-
Clarkson 1986a). The Safety in Bear
must be constructed of sturdy materi-
sons, protected categories, and quotas
Country Manual (Bromley 1985, Graf et
als and properly maintained to pre-
apply. In Alaska, polar bear hunting is
al. 1992) has been used as a reference
vent bears from entering the exclosure.
not legal, but native people may kill
text for most workshops.
The fence should be a minimum of 6
animals for subsistence. In Russia and
feet (2 m) high, and the bottom should
Svalbard, polar bears are completely
Many bear problems occur at industry
be secured to the ground or a cement
protected. In Greenland, polar bears
camps and work sites. When design-
foundation to prevent bears from lift-
are legally harvested by Inuk hunters.
ing and setting up camps, the number
ing the fence and crawling under the
Females with cubs in dens are pro-
of conflicts can be reduced by consid-
wire. Keep fence gates closed when
tected.
ering the potential bear problems.
Keeping a clean camp and reducing
not in use to prevent bears from enter-
Deterring polar bears in Alaska is
the number of attractants will reduce
ing the area.
restricted to wildlife officers because
bear problems. Once a bear has
Electric fences have been tested on
polar bears are protected by the
received a food or garbage reward
polar bears with limited success;
Marine Mammal Protection Act. This
from a camp, it will quickly associate
grounding problems during winter
policy is being questioned because it
the camp with available food. Most
months have been the primary
does not allow companies or private
bears that are habituated to human
obstacle. Davis and Rockwell (1986)
individuals to deter a bear in a prob-
food or garbage are destroyed in a
describe an electric fence they used to
lem situation. It is, however, legal for
problem bear situation. To reduce the
protect a camp during the summer
anyone to shoot a bear in defense of
number of problems and problem bear
months along the Hudson Bay coast.
life. In Canada it is legal for anyone to
deaths, careful planning and precau-
attempt to deter, and if necessary
tions should be taken.
The use of high metal platforms, such
destroy, a bear in defense of life or
as oil rig caissons, or offshore drilling
property. Any bear killed in either
A “Problem Bear Site Operations
ships, prevents bears from getting
jurisdiction must be reported to the
Plan” was developed to help indus-
access to work and living areas. Sturdy
nearest wildlife office.
trial operations better plan and pre-
metal buildings and iron bar cages
C-28

have been successfully used to store
food and equipment, and prevent
polar bear access.
Cracker shell
Cultural Methods
Regular snow removal from work and
living areas in polar bear habitat will
help make these sites safer by reducing
150 yards
potential hiding spots and increasing
visibility for personnel. Install lighting
around the work site to increase vis-
200 yards
ibility and staff safety. Proper design
and set-up of work and living sites will
help reduce potential problems. Regu-
lar camp maintenance and proper han-
dling and storage of food, wastes, and
oil products will help reduce bear
problems.
Deterrents and Frightening
Devices
Nonlethal deterrents are used on polar
Plastic slug
bears in an attempt to scare them away
rather than destroy them. Deterrents
range from snowmobiles and vehicles
to 12-gauge plastic slugs and cracker
shells. Choosing an appropriate deter-
rent will depend on the type of prob-
lem and specific location (Table 1).
Regardless of the type of deterrent
30 to 60 yards
used, all encounters with bears should
be supported by an additional person
equipped with a loaded firearm.
Graf et al. (1992) reviewed several
deterrents that are useful for polar
bears. Clarkson (1989) recommends
the use of a 12-gauge shotgun and a
“three-slug system” (cracker shell,
plastic slug, and lead slug). Deter bears
from a site as soon as they are seen in
Lead slug
the area, to prevent them from ap-
proaching closer and receiving some
type of food or garbage reward. Figure
3 identifies the appropriate distances
for deterring versus destroying a bear.
Each bear deterrent situation is differ-
ent, and depends on the bear’s behav-
ior and safety options available at the
0 to 30 yards
site. When deterring a bear with a
plastic slug, aim for the large muscle
mass area in the hind quarters (Fig. 4).
The neck and front shoulders should
be avoided to minimize the risk of hit-
ting and damaging an eye.
Fig. 3. Deterring and destroying a bear with a 12-gauge shotgun.
C-29

Table 1. Review of deterrent methods.
Method
Effectiveness
Practicality
Advantages
Limitations
Warning shots
-will not scare some bears
-practical for most situations
-readily available
-may injure bear, if not
-repeated use may decrease
where portable, short-term
-easy to use
carefully placed
effectiveness
deterrent is needed
-portable
Cracker shells
-same as for warning shots
-same as for warning shots
-same as for warning shots
-improper storage and/or
-should not be relied on for
old stock can misfire
personal protection
-may be a fire hazard
Blank pistol
-same as for cracker shell
-same as for warning shots
-safe
-may be a fire hazard
Screamer/banger
-loud, unusual, and
prolonged noise
-long range 100+ yards
Pencil flare gun
-same as for cracker shell
-same as for warning shots
-same as for warning shots
-same as for cracker shells
Propane cannon
-will protect livestock and
-practical as immediate
-easy to set up and use
-restricted to isolated
apiaries
response to emergency
-portable
areas as sound carries
situations
long distance
12-gauge
-very effective though some
-suitable for most problem
-can be fired from a
-may injure bear if used
plastic slugs
bears not deterred
bear situations
12-gauge shotgun
at a range closer than
-portable
recommended
Rubber bullet
-very effective
-useful in most situations
-bears do not react
-use limited to renewable
(38 mm)
when a Renewable Resource
aggressively
resource officers and
Officer or R.C.M.P. can be
R.C.M.P. in Canada
contacted
-intensive training and
practice necessary
-may injure bear if shot
not placed properly
-special gun required
Electric
-fence built to proper
-suitable for temporary, semi-
-permanent deterrent
-effort required for
fence
specifications will keep out
permanent, and permanent
method
installation
polar bears
installations
-24 hours protection
-regular maintenance
required
Capsaicin sprays
-effective for polar bears in
-portable
-readily available
-may not be useful in all
some circumstances
-useful as a backup for other
-portable
situations (wind)
-should not be relied on for
deterrent methods
-easy to use
-limited range (6-8 yards)
personal protection
-useful while traveling or in
-not reliable in sub-zero
small camp areas where
temperatures
other deterrents not allowed
Vehicles
-engine noise often frightens
-useful while traveling or
-easy if vehicle is
-may be hazardous to
(snowmachines,
bears away
in small camps where
accessible
persons and bears if not
all terrain vehicles,
-chasing bears for a short
vehicles or helicopters
used properly
helicopters)
distance is effective
are used
Air horns
-same as for warning shots
-same as for warning shots
-same as for warning shots
-not reliable in cold
(boat horns)
and cracker shells
temperatures
-may provoke aggressive
or curious reaction
-source of noise is from
person
Dogs
-specially trained dogs may be
-suitable for camps of all sizes
-easy
-untrained dogs can
effective in some cases
aggravate a bear and/or
-not reliable
lead it back to camp
-dogs can be killed
-require a responsible
handler
Bear monitors
-can be highly effective if
-especially useful at large,
-flexible
-need several monitors
experienced with bears,
established camps
for 24-hour protection
deterrents, and firearms
-need good
communication
C-30

Table 2. Review of bear detection systems.
Method
Practicality
Effectiveness
Advantages
Limitations
Trip-wire fence
-small or temporary camps
-100% successful in field
-small, light, portable
-may be triggered by
tests
-24-hour protection
other animals
-inexpensive
-must be reset manually
-easy to set up and operate
-requires minimal
equipment
Microwave motion
-large, semipermanent, and
-100% successful in field
-24 hour protection
-perimeter limitation of
detection system
permanent camps
tests
-easy to install and
450 yards for single unit
maintain
-may be triggered by
-resets automatically
other animals
-powered by AC current
-relatively expensive
or 12V batteries
-not easily moved
-site levelling may be
required
-units must be “bear-
proofed”
Dogs
-most situations (requirements
-inconsistent results
-simple
-protection may be
for dogs must be met, refer
-inexpensive
inconsistent
to text)
-portable
-dog may be mauled or
killed
-dogs may attract bears
-some risk involved until
you have seen a dog’s
reaction to bears
Bear monitors
-medium to large semi-
-effectiveness depends on
-flexible
-thorough training
permanent and permanent
experiernce and training
-provide protection as
necessary to obtain
camps
of monitor
well as warning
maximum effectiveness
Infra-red system
-potentially useful for large
-100% successful in
-24 hour protection
-expensive
sites
preliminary field tests
-flexible
-must be operated by
-useful where unstable
trained personnel
ground/ice conditions
-poor functional
exist
operating distance
-portable
-poor video image
Conventional
-potentially useful for most
-have been successfully used
-easy to use
-effectiveness to detect
security system
situations
for detecting people
-portable
bears has not been
-have not been field-tested on
-flexible
determined
bears
-some systems are
expensive
Detection Systems
both as a detection and deterrent
Fumigants
system.
Detecting a polar bear that is
No fumigants are registered for use on
approaching a work or living area is
polar bears.
Repellents
an important part of handling bear
problems. Bear detection systems
Capsaicin (oleoresin of capsicum or
Trapping
range from a simple tripwire to more
concentrated red pepper) spray has
Live traps used to capture polar bears
technical electronic monitoring devices
been tested and used on black and
include culvert or barrel traps and foot
(Table 2). If a bear is approaching a
grizzly bears (Hunt 1984), but has not
snares. Both have been used to capture
work or living area, the personnel on
yet been tested on polar bears. It may
all three bear species in North
site should have time first to ensure
become more popular where restric-
America. The culvert trap has been
their safety and second to prepare to
tions on firearms are in place. Capsai-
used to capture polar bears at Chur-
deter the bear. Detection systems must
cin needs to be scientifically tested
chill, Manitoba, and in the eastern
be properly installed and maintained
before it can be formally recom-
Northwest Territories. It can also be
to be effective. If bear problems are
mended for polar bear protection.
used for short-term holding and trans-
rare, a system that is too technical or
porting of captured polar bears. Foot
difficult to maintain will soon be
Toxicants
snares were used in polar bear
neglected. Bear monitors and dogs
No toxicants are registered for use on
research in the early 1970s and are
should have previous experience with
polar bears.
useful in some situations today. A
bears. An experienced bear dog can act
C-31

detailed description of using the cul-
vert trap and foot snare is found in the
Deterrent
Deterrent or lethal
Black Bears chapter in this handbook.
In the early to mid-1900s, large leghold
traps were used along the Arctic coast.
These are no longer used today.
Shooting
Unfortunately, some bear-people con-
flicts require that problem bears be
shot. Polar bears can be aggressive in
attempting to obtain food, especially if
they are in poor condition and near
starving. If it is necessary to destroy a
polar bear, it should be done as effi-
ciently and humanely as possible. The
12-gauge pump action shotgun with
Fig. 4. Recommended deterrent and lethal hit locations on bears.
lead slugs is an effective weapon for
destroying a bear at close range (less
Darting from a helicopter (Bell 206 Jet
are captured or immobilized and not
than 100 feet [30 m]). It can also be
Ranger or similar size), has been used
destroyed are usually held in a culvert
used to deter a polar bear. High-
for research and problem bear man-
trap or other suitable facility. Bears can
powered rifles of .30-06 or larger cali-
agement. The helicopter should be
be transported from a problem site
ber are also effective in destroying
equipped with a shooting window and
with a culvert trap and released at
bears. A rifle used for bear protection
have sling capabilities for moving
another location if a road system
should be equipped with open sights
bears. The helicopter should slowly
exists. Road systems are limited in the
for close-range use.
approach the bear from behind at an
arctic and relocating problem bears
Generally, if a bear is beyond 150 feet
altitude of 20 to 30 feet (6 to 10 m).
with culvert traps is usually not an
(45 m), destroying it is not necessary
Shooting distance from a helicopter is
effective option. In most cases, cap-
because the bear can be deterred
usually less than 30 feet (10 m). Bears
tured and immobilized bears need to
before it comes closer. If it is necessary
should be darted in the large muscle
be relocated by helicopter. Take pre-
to destroy a bear beyond 100 feet (30
areas of the neck, shoulder, or upper
cautions to ensure that bears are not
m), a high-powered rifle will be more
midback. Several immobilizing drugs
injured or suffering from hyperthermia
accurate and have more penetration
have been used on polar bears in the
when transporting them in a cargo net
energy. Whether a shotgun or rifle is
past, however, Telazol is presently
below a helicopter.
used, bears should be shot in the
considered the most effective. Telazol
In Churchill, Manitoba, polar bears are
chest/vital organ area (Fig. 4). Hand-
is a safe and predictable drug to work
captured in or near the town limits,
guns are not recommended for bear
with because there is a wide range of
held in a polar bear holding facility
protection or for destroying problem
tolerance to high dosages, the reactions
and then flown out to an area north of
bears. Proper training and practice is
of darted bears can be easily inter-
Churchill and released. Capturing and
necessary to effectively use a firearm
preted, and the bears are able to ther-
holding the bears in the “polar bear
for bear protection or for destroying a
moregulate while immobilized.
jail” prevents these bears from causing
bear.
Dosages of 8 to 9 mg/kg or greater are
problems while they are waiting for
usually necessary to fully immobilize a
the ice to form on Hudson Bay. Bears
Other Methods
polar bear for measuring and tagging.
kept in a holding facility can be given
Immobilization time for adult bears
Drugging/Immobilization. Polar
water, but food is not recommended
depends on the injection site and
bears are often immobilized in prob-
because the bears may begin to associ-
weight of the bear. On the average, a
lem situations. Bears can be drugged
ate people and the holding facility with
bear will be immobilized in 4 to 5 min-
while free ranging by darting them
food. Although an expensive program,
utes after the first injection of Telazol.
from the ground or from a helicopter,
the polar bear jail at Churchill has
Cubs of the year can be immobilized
or darting after capture in a culvert
reduced the number of polar bear
by hand or with a jabstick after being
trap or foot snare. Darts can be fired
problems and polar bear mortalities.
captured on or near their immobilized
from a rifle or pistol. A jab stick can be
mother.
Relocating problem bears usually does
used to immobilize bears captured in a
not solve the problem since they often
culvert trap, but is not recommended
Holding, Transporting, and
return, sometimes from considerable
for bears in a foot snare.
Relocating. Problem polar bears that
C-32

distances. Polar bears that are waiting
Acknowledgments
Clarkson, P. L. 1989. The twelve-gauge shotgun:
along a coastline for ice to form should
a bear deterrent and protection weapon.
Pages 55-59 in M. Bromley, ed. Bear-people
be moved in the general direction they
We gratefully acknowledge the following for
conflicts. Proc. Sym. Manage. Strategies.
would normally travel. Most of the
their continued support of our research on bears
Northwest Territ. Dep. Renew. Resour.,
polar bears released north of Churchill
in general, and polar bears in particular: the
Yellowknife.
Northwest Territories Department of Renewable
travel out on the sea ice and do not
Resources, the Canadian Wildlife Service, Polar
Clarkson, P. L., and P. Gray. 1989. Presenting
return to the townsite.
Continental Shelf Project, Manitoba Department
safety in bear country information to
of Natural Resources, World Wildlife Fund
industry and the public. Pages 203-207 in M.
Economics of Damage
(Canada), Northern Oil and Gas Assessment
Bromley, ed. Bear-people conflicts. Proc.
Program, and the Natural Sciences and Engi-
Sym. Manage. Strategies. Northwest Territ.
and Control
neering Research Council of Canada. All people,
Dep. Renew. Resour., Yellowknife.
organizations, government departments, and
Clarkson, P. L., P. A. Gray, J. E. McComiskey, L.
No specific studies or reports have
industry previously involved in the Northwest
R. Quaife, and J. G. Ward. 1986a. Managing
Territories’ “Safety in Bear Country Program”
documented the economic costs of
bear problems in northern development
are thanked for their past concern and support.
polar bear damage in the Arctic. Past
areas. Northern Hydrocarbon Development
L. Graf and K. Embelton assisted in word-
Environment Problem Solving. Proc. Ann.
polar bear problems have ranged in
processing and editing.
Meeting Int. Soc. Petroleum Ind. Biol.
cost from nothing to several thousands
Tables 1 and 2 were adapted from Graf et al.
10:47-56.
of dollars. With the remote locations of
(1992).
Clarkson, P. L., G. E. Henderson, and P. Kraft.
camps and communities and the
Figure 1 drawn by Clint Chapman, University of
1986b. Problem bear site operation plans.
expense of transporting food and
Nebraska.
Northwest Territ. Dep. Renew. Resour.,
products in the Arctic, replacement
Yellowknife. 12 pp.
Figure 2 was adapted from Sterling (1988) by
costs are high. Lost work time of per-
Dave Thornhill, University of Nebraska.
Clarkson, P. L., and L. Sutterlin. 1983. Bear
sonnel and programs can also be sub-
essentials: a source book and guide to
Figures 3 and 4 are from Clarkson (1989).
stantial because of polar bear
planning bear education programmes.
Faculty Environ. Design, Univ. Calgary.
problems. In September 1983, Esso
69 pp.
Resources Canada had to suspend
For Additional
drilling until a wildlife officer could
Davis, J. C., and R. F. Rockwell. 1986. An electric
Information
fence to deter polar bears. Wild. Soc. Bull.
drug and remove a bear that had hap-
14:406-409.
pened onto the artificial island, costing
Amstrup, S. E. 1986. Research on polar bears in
DeMaster, D. P., and I. Stirling. 1981. Ursus
Esso about $125,000. A similar incident
Alaska, 1983-1985. Proc. Working Meeting of
maritimus. Mammal. Species 145:1-7.
occurred in 1985, and cost Esso
the IUCN/SSC Polar Bear Specialist Group.
approximately $250,000 in lost work
9:85-108.
Fleck, S., and S. Herrero. 1988. Polar bear
conflicts with humans. Contract Rep. No. 3.
time.
Arco Alaska, Inc. 1990. Fireweed No. 1
Northwest Territ. Dep. Renew. Resour.,
exploratory well. Polar Bear/Personnel
Yellowknife. 155 pp.
Hiring bear monitors can cost up to
Encounter and Monitoring Plans. 16 pp.
$250 per day to protect personnel, a
Graf, L. H., P. L. Clarkson, and J. A. Wagy. 1992.
Banfield, A. W. F. 1974. The mammals of
camp, or an industrial site from polar
Safety in bear country: a reference manual,
Canada. Univ. Toronto Press, Toronto.
rev. ed. Northwest Territ. Dep. Renew.
bears. The cost of government staff
438 pp.
Resour., Yellowknife. 135 pp.
and programs that are responsible for
Bromley, M. 1985. Safety in bear country: a
Gray, P. A., and M. Sutherland. 1989. A review
handling polar bear problems will
reference manual. Northwest Territ. Dep.
of detection systems. Pages 61-67 in M.
depend on the number of problems.
Renew. Resour., Yellowknife. 120 pp.
Bromley, ed. Bear-people conflicts. Proc.
Churchill, Manitoba, has the most
Symp. Manage. Strategies. Northwest Territ.
Bromley, M., ed. 1989. Bear-people conflicts.
intensive government program to
Dep. Renew. Resour., Yellowknife.
Proc. Symp. Manage. Strategies Northwest
handle polar bear problems. This pro-
Territ. Dep. Renew. Resour., Yellowknife.
Hunt, C. L. 1984. Behavioral responses of bears
gram costs the Manitoba government
246 pp.
to tests of repellents, deterrents, and aversive
approximately $120,000 per year (M.
conditioning. M.S. Thesis. Montana State
Calvert, W., I. Stirling, M. Taylor, L. J. Lee, G. B.
Univ., Bozeman. 136 pp.
Shoesmith, pers. commun.).
Kolenosky, S. Kearney, M. Crete, B. Smith,
and S. Luttich. 1991. Polar bear management
Hygnstrom, S. E. 1994. Black bears. in S. E.
Purchasing detection and deterrent
in Canada 1985-87. Rep. to the IUCN Polar
Hygnstrom, R. M. Timm and G. E. Larson,
equipment and educating people on
Bear Specialist Group. Proc. IUCN/SSC
eds. Prevention and Control of Wildlife
Polar Bear Specialists Group. IUCN Report
the proper procedures to prevent and
Damage. Coop. Ext., Univ. Nebraska,
No. 7:1-10.
Lincoln.
handle bear problems will cost compa-
Clarkson, P. L. 1986a. Safety in bear country
nies and agencies. These costs, how-
Lewis, R. W., and J. A. Lentfer. 1967. The
instructors’ guide. Northwest Territ. Dep.
vitamin A content of polar bear liver: range
ever, are minimal when compared to
Renew. Resour., Yellowknife. 32 pp.
and variability. Compar. Biochem. Physiol.
personnel safety, replacement costs of
22:923-926.
Clarkson, P. L. 1986b. Eureka and Mould Bay
property in the Arctic, and long-term
weather stations problem bear site
Lunn, N. J., and I. Stirling. 1985. The significance
polar bear conservation concerns.
evaluation and recommendation. Northwest
of supplemental food to polar bears during
Territ. Dep. Renew. Resour., Yellowknife.
the ice-free period of Hudson Bay. Can. J.
42 pp.
Zool. 63:2291-2297.
C-33

Meehan, W. R., and J. F. Thilenius. 1983. Safety
Stirling, I., and A. E. Derocher. 1990. Factors
in bear country: protective measures and
affecting the evolution and behavioural
bullet performance at short range. US Dep.
ecology of the modern bears. Int.. Conf. Bear
Agric. For. Serv. Gen. Rep PNW-152. 16 pp.
Res. Manage. 8:189-204.
Rodahl, K. 1949. Toxicity of polar bear liver.
Stirling, I., and M. A. Ramsay. 1986. Polar bears
Nature 164:530.
in Hudson Bay and Foxe Basin: present
knowledge and research opportunities.
Ramsay, M. A., and I. Stirling. 1988.
Pages 341-354 in I. P. Martini, ed. Canadian
Reproductive biology and ecology of female
Inland Seas. Elsevier Sci. Publ., Amsterdam.
polar bears Ursus maritimus. J. Zool. London.
494 pp.
214:601-634.
Stirling, I., D. Andriashek, and W. Calvert. 1993.
Schliebe, S. 1991. Polar bear management in
Habitat preferences of polar bears in the
Alaska. Report to the IUCN Polar Bear
western Canadian Arctic in late winter and
Specialist Group. Proc. IUCN/SSC Polar
spring. Polar Record 29:13-24.
Bear Specialists Group. IUCN Rept. No.
7:62-69.
Stirling, I., C. Spencer, and D. Andriashek. 1989.
Immobilization of polar bears Ursus
Schweinsburg, R. E., L. J. Lee, and P. B. Latour.
maritimus with Telazol in the Canadian
1982. Distribution, movement, and
Arctic. J. Wildl. Diseases. 25:159-168.
abundance of polar bears in Lancaster
Sound, Northwest Territories. Arctic
Struzik, E. 1987. Nanook: in the tracks of the
35:159-169.
great wanderer. Equinox Jan.-Feb. 1987.
pp. 18-32.
Stenhouse, G. B, L. J. Lee, and K. G. Poole. 1988.
Some characteristics of polar bears killed
Urquhart, D. R., and R. E. Schweinsburg. 1984.
during conflicts with humans in the
Polar bear: life history and known
Northwest Territories. Arctic 41:275-378.
distribution of the polar bear in the
Northwest Territories up to 1981. Northwest
Stirling, I. 1975. Summary of a fatality involving
Territ., Dep. Renew. Resour., Yellowknife.
a polar bear attack in the Mackenzie Delta,
69 pp.
January 1975. Can. Wildl. Serv. Polar Bear
Proj. Spec. Rep. 89. 2 pp.
Uspenskii, S. M. 1977. The polar bear. Nauka,
Moscow, 107 pp. (English trans. by Canadian
Stirling, I. 1988a. Polar bears. Univ. Michigan
Wildl. Serv., 1978).
Press., Ann Arbor. 220 pp.
Stirling, I. 1988b. Attraction of polar bears Ursus
maritimus to offshore drilling sites in the
Editors
eastern Beaufort Sea. Polar Record
Scott E. Hygnstrom
24(148):1-8.
Robert M. Timm
Gary E. Larson
C-34

Document Outline
  • Summary
  • Identification
    • Fig. 1
  • Range
    • Fig. 2
  • Habitat
  • Food Habits
  • General Biology, Reproduction, and Bahavior
  • Damage and Damage Identification
  • Legal Status
  • Damage Prevention and Control Methods
    • Preventing Polar Bear-People Conflicts
    • Exclusion
    • Cultural Methods
    • Deterrents and Frightening Devices
      • Table 1
      • Fig. 3
      • Fig. 4
    • Detection Systems
      • Table 2
    • Repellents
    • Toxicants
    • Fumigants
    • Trapping
    • Shooting
    • Other Methods
      • Drugging/Immobilization
      • Holding, Transporting, and Relocating
  • Economics of Damage and Control
  • Acknowledgments
  • For Additional Information

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